The Usun Apau Plateau

Abstract

/iN oxford expedition went out to Sarawak in July 1955 to spend six months ZJLexploring and surveying in a remote part of Borneo, in one of the last genuinely unexplored parts of South-east Asia. The Usun Apau is an old volcanic plateau at the head-waters of the Rajang, Sarawak's largest river. Until 1951 its existence was unknown but in that year an expedition organized by the Curator of the Sarawak Museum, Mr. Tom Harrisson, discovered this extensive upland area. Mountainous, thickly covered by jungle and giving rise to many waterways, the Usun Apau is uninhabited except for a few groups of nomadic Penans. It remained unknown for so long because all the rivers flowing from it pass through great series of cataracts and gorges, falling 1000 feet or more before reaching the navigable stretches of water nearer the coast. The expedition planned to spend six months in the area of this plateau carrying out a general scientific survey. There were four members and the work to be done included: geological survey; zoological collections; forestry survey and collections; archaeological excavations; ethnological study of the nomadic Penans; general surveying; meteorological observations; filming; the collection of soil samples. Due to the remoteness of the plateau the major problem confronting the expedition was that of supplies, but this difficulty was largely overcome by two airdrops with a three-month interval between them. The expedition is most grateful for the support given to it by the Royal Geographical Society, Oxford University, the Sarawak Government, Sarawak Oilfields (Shell) Ltd., as well as many other societies and commercial concerns. The area covered by the expedition was extensive, ranging from the fertile and historically important Plieran valley in the south, across the more barren volcanic plateau, to Kalulong mountain in the north. About 8000 specimens?zoological, botanical, archaeological and geological?were collected as well as a selection of Penan goods. These have been distributed in various museums and are being worked on. The work of the expedition can really be divided into two?the collec? tions for scientific comparison purposes and the surveying and the archaeological and ethnological studies throwing some light on the early history of the Usun Apau. The Oxford Expedition was the fourth party to work on the Usun Apau and in the Plieran valley. Some of the ground covered was completely new but much had been visited in 1951, 1954 and April 1955. The Usun Apau was first brought to light when Mr. Tom Harrisson and Mr. David Leach, Director of Sarawak Lands and Surveys (since retired), made the journey mentioned above from the upper Baram to the Plieran and then down to the Rajang, in 1951. They found that a blank on the map of 1600 square miles was in reality an upland area of mountains, plateau and deep river valleys. They were the first Europeans to cross the Usun Apau and contact the Plieran Penans, and Mr. Harrisson discovered the existence of old longhouse sites, and so revealed the historical importance of the area. In 1954 a combined geological expedition composed of Dr. G. Whittle of Colonial Geological Surveys and Dr. H. Kirk of the Sarawak Geological Surveys went into the Plieran valley. An airdrop of supplies was made to them at Long Luar?the junction of the Luar and Plieran rivers?where they had cut a clearing. Subsequently the Oxford Expedition used this site for its base camp and the first supply